5.8 gamma correction
once the pixel values have been computed, we need to display them on a monitor. in the early years of digital imaging, cathode-ray tube (CRT) monitors were almost exclusively used. CRT monitors exhibit a power law relationship between input voltage and display radiance, which turns out to nearly match the inverse of light sensitivity of the human eye [1028]. the consequence of this fortunate coincidence i sthat an encoding proportional to CRT
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